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        \begin{tabular}{|m{1.2em}<{\centering}|m{1.2em}<{\centering}|m{1.2em}<{\centering}|m{1.2em}<{\centering}|m{1.2em}<{\centering}|}
            \hline 
            {\ }{}  & a & b & $\ldots$ & \ooalign{$\bigvee$\cr$-$} \\ \hline
            1 & 3 & 6 & $\ldots$ & no \\ \hline
            $\ldots$ & $\ldots$ & $\ldots$ & $\ldots$ & $\ldots$ \\ \hline
            4 & no & no & $\ldots$ & ok \\ \hline
            5 & no & no & $\ldots$ & ok \\ \hline
        \end{tabular}
    };
    \node  (+2) at([xshift=-6.9em,yshift=-2.125em]Figure1.north) {+};
    \node  (-4) at([xshift=-6.8em,yshift=-4.625em]Figure1.north) {-};
    \node  (-5) at([xshift=-6.8em,yshift=-5.75em]Figure1.north) {-};
    \draw ([xshift=-5.95em,yshift=-0.05em]Figure1.north) edge ([xshift=-3.55em,yshift=-1.25em]Figure1.north);

        
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